internal override void Interpret(IInterpretContext ctx)
{
if (!ctx.State.ContainsKey("CurrentIf"))
{
ctx.State.Add("CurrentIf", new Stack <bool>());
}
Stack <bool> CurrentIf = (Stack <bool>)ctx.State["CurrentIf"];
Stack <object> CurrentTag = ctx.CurrentTag;
IfTagType? currentIfTagType = CurrentTag.Count > 0 && CurrentTag.Peek() is IfTagType
? (IfTagType?)CurrentTag.Peek()
: null;
bool val = false;
int ifDepth = 0;
bool found = false;
switch (this.TagType)
{
case IfTagType.If:
val = this.Expression.EvaluateAsBoolean(ctx);
CurrentTag.Push(IfTagType.If);
CurrentIf.Push(val);
if (val)
{
ctx.MoveNext();
}
else
{
// move forward to the next ELSE or ELSE IF or ENDIF
found = false;
ifDepth = 0;
do
{
ctx.MoveNext();
MarkupBase m = ctx.CurrentMarkup;
if (m is IfTagMarkup)
{
IfTagType loopIfTagType = ((IfTagMarkup)m).TagType;
if (loopIfTagType == IfTagType.If)
{
ifDepth++;
}
else
{
if (ifDepth > 0)
{
// ignore tags that are either an elseif or else
// if its an endif, then decrement the ifDepth
if (loopIfTagType == IfTagType.EndIf)
{
ifDepth--;
}
}
else
{
found = (
loopIfTagType == IfTagType.ElseIf ||
loopIfTagType == IfTagType.Else ||
loopIfTagType == IfTagType.EndIf
);
}
}
}
} while (!found || ctx.ListPosition >= ctx.ParseList.Count);
}
break;
case IfTagType.ElseIf:
// make sure we have a logically correct parent
if (currentIfTagType == null ||
(
currentIfTagType != IfTagType.If &&
currentIfTagType != IfTagType.ElseIf
)
)
{
throw new ImpressionInterpretException("Expected an IF or ELSEIF before ELSE", this);
}
// if the current IF was false, process this ELSEIF
if (!CurrentIf.Peek())
{
val = this.Expression.EvaluateAsBoolean(ctx);
// remove current tag, add "elseif"
CurrentTag.Pop();
CurrentTag.Push(IfTagType.ElseIf);
if (val)
{
// add us to the if
CurrentIf.Pop();
CurrentIf.Push(val);
ctx.MoveNext();
return;
}
}
// move forward to the next ELSE IF or ENDIF
found = false;
ifDepth = 0;
do
{
ctx.MoveNext();
MarkupBase m = ctx.CurrentMarkup;
if (m is IfTagMarkup)
{
IfTagType loopIfTagType = ((IfTagMarkup)m).TagType;
// if its an if, then increment the ifDepth
if (loopIfTagType == IfTagType.If)
{
ifDepth++;
}
else
{
if (ifDepth > 0)
{
// ignore tags that are either an elseif or else
// if its an endif, then decrement the ifDepth
if (loopIfTagType == IfTagType.EndIf)
{
ifDepth--;
}
}
else
{
found = (loopIfTagType == IfTagType.ElseIf ||
loopIfTagType == IfTagType.Else ||
loopIfTagType == IfTagType.EndIf);
}
}
}
} while (!found || ctx.ListPosition >= ctx.ParseList.Count);
break;
case IfTagType.Else:
// make sure we have a logically correct parent
if (currentIfTagType == null ||
(currentIfTagType != IfTagType.If &&
currentIfTagType != IfTagType.ElseIf))
{
throw new ImpressionInterpretException("Expected an IF or ELSEIF before ELSE", this);
}
// if the last if wasn't true then check this otherwise, just skip
if (!CurrentIf.Peek())
{
// rejig the if
CurrentIf.Push(!CurrentIf.Pop());
// remove current tag, add "else"
CurrentTag.Pop();
CurrentTag.Push(IfTagType.Else);
// move to the next markup
ctx.MoveNext();
}
else
{
// move to the next markup
//ctx.MoveNext();
// move forward to the next ENDIF at this level
found = false;
ifDepth = 0;
do
{
ctx.MoveNext();
MarkupBase m = ctx.CurrentMarkup;
if (m is IfTagMarkup)
{
IfTagType loopIfTagType = ((IfTagMarkup)m).TagType;
// if its an if, then increment the ifDepth
if (loopIfTagType == IfTagType.If)
{
ifDepth++;
}
else
{
if (ifDepth > 0)
{
// ignore tags that are either an elseif or else
// if its an endif, then decrement the ifDepth
if (loopIfTagType == IfTagType.EndIf)
{
ifDepth--;
}
}
else
{
found = loopIfTagType == IfTagType.EndIf;
}
}
}
} while (!found || ctx.ListPosition >= ctx.ParseList.Count);
}
break;
case IfTagType.EndIf:
// make sure we have a logically correct parent
if (currentIfTagType == null ||
(currentIfTagType != IfTagType.If &&
currentIfTagType != IfTagType.ElseIf &&
currentIfTagType != IfTagType.Else))
{
throw new ImpressionInterpretException("Expected an IF, ELSEIF or ELSE before ENDIF", this);
}
// rejig the if
CurrentIf.Pop();
// remove current tag
CurrentTag.Pop();
ctx.MoveNext();
break;
}
}
public IfTagMarkup(IfTagType tagType, ExpressionMarkup expression, string markup, int lineNumber, int charPos)
: base(expression, markup, lineNumber, charPos)
{
this.TagType = tagType;
}
public IfTagMarkup(IfTagType tagType, ExpressionMarkup expression, string markup, int lineNumber, int charPos)
: base(expression, markup, lineNumber, charPos)
{
this.TagType = tagType;
}
